Diols from resin acids



United States Patent 3,499,006 DIOLS FROM RESIN ACIDS Bernard A. Parkin,In, Lake City, Fla., Hugh B. Summers, Jr., Savannah, Ga., and Glen W.Hedrick, Lake City, Fla., assignors to the United States of America asrepresented by the Secretary of Agriculture N0 Drawing. Originalapplication June 30, 1966, Ser. No. 562,951. Divided and thisapplication Apr. 11, 1968, Ser. No. 738,750

Int. Cl. C07c 173/00 US. Cl. 260345.2 3 Claims ABSTRACT OF THEDISCLOSURE This invention relates to a method for preparing diols frompine gum resin acids via a Diels-Alder type formaldehyde-resin acidadduct and to the diols so prepared. The unsaturated product diols areuseful for preparing protective coatings. The saturated product diolsare useful in the preparation of polyurethane teams and rubbers.

An non-exclusive, irrevocable, royalty-free license in the inventionherein described, throughout the world tor all purposes of the UnitedStates Government, with the power to grant sublicenses for suchpurposes, is hereby granted to the Government of the Uni-ted States ofAmerica.

This application is a division of Ser. No. 562,951, filed June 30, 1966.

:This invention relates to a method for the preparation of diols frompine gum resin acids and to the products so produced. More specifically,it deals with a process for first forming a formaldehyde-levopimaricacid add-net (II) and, subsequently, converting this adduct to6-(hydroxymethyl) abietic acid (III), 6-(hydroxymethyl) dihydroabicticacid (IV), G-(hydroxymethyl) tetrahydroabiet-inol (V), 6-(hydroxymethyl)abietinol (VI), and to the formalde'hyde adduct of abietinol (VII). The6-(hydroxymethyl) a-bietinol (VI) is useful in the preparation ofprotective coatings and has the air drying capacity of rosin. Thesaturated diol (V) may be prepared from the other compounds asintermediates or directly from the adduct (II) in one step. Thesaturated diol is useful in the preparation of polyurethane foam-s andrubbers. Most important, when the saturated diol is used as a partialreplacement for polyethylene glycols and/or polypropylene glycols in theproduction of polyurethanes, the resultant films and coatings haveimproved hardness, toughness and are clear and colorless.

The term pine gum, as used in this specification and the claims, relatesto crude pine gum and particularly to one of the main components ofcrude pine gum, levopimaric acid, which is present in the amountsranging from about 18 to 30 weight percent. Since levopima-ric acid isthermally unstable and is lost in the conversion of pine gum into rosin,levopimaric acid will be referred to below as 3,499,006 Patented Mar. 3,1970 ice a resin acid. The structure and numbering system of levopimaricacid follows:

Levopimaric Acid (1) The nomenclature is that of Fiese-r and Fieser(Natural Products Related to Phenanthrene by Fieser and Fieser, ThirdEdition, 1949, page 40. Published by Reinhold Publishing Corporation,New York, NY.)

As noted above, levopimaric acid (I) constitutes about one-fifth of thetotal acid content of pine gum. As will be seen from the chemicalstructure, it contains double 'bonds at the 6-7, 8-8a positions. Thisconjugated system reduces its resistance to the heat required in thedistillation of turpentine. Consequently, the residue (rosin) containslittle, if any, levopimaric acid.

It has been observed that upon heating levopimaric acid (I) withformaldehyde under certain conditions, a hydroxy acid was obtained whichgave an ultraviolet (UV) absorption spectrum almost identical in formwith that of abietic acid, but with a principal maximum at 243millimicrons instead of the expected 241 milli-microns. Rearrangement toan abietic-type double-bond system had apparently taken place withsubstitution of a methylol group on a carbon of the conjugateddouble-bond system.

Substitution of a methylol group on a carbon of the conjugateddoublebond system of abietic acid should according to Woodward rules,have given a shift of the UN. maximum to 246 millimicrons. Such a shiftwas observed by E. E. Royals and J. T. Greene (J. Org. Chem, 23, 5 1,437(1958)) as a result of the P-rina reaction on a-bietic acid.

However, by careful control of the reaction conditions and theconditions of product isolation, we isolated a crystalline intermediatewhich showed no UV. absorption above 210 milli-microns and contained nofree hydroxyl group. This product resulting from the Diels-Alder-typeaddition of formaldehyde to levopimaric acid is shown below and will bedesignated as adduct (II), Diels-Alder adduct (II), or just (II). Thestructural formula of adduct (II) is i. A t ll O O OH Adduct (II) o 13015 20 mm.

Purified adduct (II) is somewhat unstable, and is easily 3O converted to-hydroxymethylabietic acid (III) on heating, or by treatment at roomtemperature with dilute mineral acids.

The structural formula for (III) is II dilute acid mineralG-hydroxymethylabietic acid (111) G-hydroxymethyldihydroabietic acid(IV) When IV is hydrogenated over a copper chromite catalyst, the lastdouble bond is removed and, simultaneously,

4 the carboxylic group is converted to a hydroxymethyl group. Theresulting product is 6-hydroxymethyltetrahydroabietinol (V) frequentlyreferred to below as (diol) (abietyl glycol), or simply as (V). This isa saturated glycol.

The structural formula for (V) is CHQOHG-hydroxymethyltetrahydroabietinol (V) (Diol) The abietyl glycol (V) maybe accomplished in a single step by hydrogenating the adduct (II) bymeans of the catalyst copper chromite.

It is a prime object of our invention to convert, stepwise, resin acidsfrom pine gum to 6-hydroXy-methyltetrahydroabietinol (diol) (V).

It is a further object to first prepare the levopimaricacid-formaldehyde adduct (II) from the purified levopimaric acid and/ orpine gum.

It is a still further object to convert the levopimaricacid-formaldehyde adduct by cleavage of the internal ether andrearrangement in dilute acid solution to G-hydroxyrnethylabietic acid(III).

It is a still further object to convert, through hydrogenation in thepresence of a palladium-on-carbon (5%) catalyst, the6-hydroxymethylabietic acid to 6-hydroxymethyldihydroabietic acid (IV).

It is a still further object to convert, through hydrogenation in thepresence of a copper-chromite catalyst the 6-hydroxymethyldihydroabieticacid to the diol (V). This diol is a saturated compound and, as notedabove, may be combined in varying proportions with other saturatedglycols such as polyethylene glycol (e.g., polyethylene glycol 20 0) orwith polypropylene glycol (e.g. polypropylene glycol 2000), in thepreparation of polyurethane foams and rubbers.

It is also Within the scope of our invention to convert, throughreduction by means of lithium aluminum hydride and alkaline hydrolysis,the carboxylic acid group of Adduct (H) to the novel l-hydroxymethylform of the adduct which is designated herein as (VII). The latter (VII)is readily converted to (VI) by means of dilute mineral acid, and (VI)can be converted to fi-hydroxymethyltetrahydroabietinol (V) (diol) bythe copper-chromite catalyst mentioned above.

The details of these various objects are described in the accompanyingexamples wherein temperatures are in centrigrade degrees; B.P. isboiling point, mm. is millimeters pressure (mercury); OHE or (ohe) ishydroxyl equivalent and was determined by the method of C. L. Ogg, W. L.Porter, and C. O. Willits, Ind. Eng. Chem., anal, ed, 17, 394 (1945).The procedure follows:

MDGED INDICATOR SOLUTION Consists of one part of 0.1% aqueous cresol redneutralized With sodium hydroxide and three parts of 0.1% thyrnol blueneutralized with sodium hydroxide.

PROCEDURE Weigh a sample containing about 1-2.5 miiliequivalents ofhydroxyl and introduce into a glass-stoppered iodine flask. Add 3.00 ml.of the freshly prepared acetylating reagent (1 volume of aceticanhydride to 3 volumes of pyridine) using a pipet or some other means ofaccurate measurement. Moisten the glass stopper with pyridine and seatloosely, and then place the flask on a steam bath and heat for 45minutes. Add 5-6 ml. of water and swirl to mix thoroughly. Continueheating for 2 minutes and then cool in tap water. Rinse down the stopperand sides of the flask with ml. of butyl alcohol, and then add a fewdrops of indicator and titrate with the standard sodium hydroxide (0.5N). Make a blank determination on the reagent simultaneously and similarin all respects.

If the sample contains any free acid or alkali, this should bedetermined separately and corrected for in the calculation.

Calculation Hydroxyl equivalent (OI-IE) Weight of sample in mg. [titerof blank (ml.)titer of sample (mg.)]

where N=normality of NaOH solution.

The following terms are defined for subsequent use in the disclosurewhich follows:

(n.e.) or ne is neutralization equivalent and for resin acids is equalto the molecular weight; HaE is active hydrogen equivalent, i.e., thegrams of the sample required to evolve 1 mole of hydrogen on treatmentwith excess lithium aluminum hydride (LiAlH p.s.i.g. or p.s.i. is poundsper square inch gage; mu is millimicrons; Pd-C(5%) is 5%palladium-on-carbon catalyst (Girdler G81-C); n.m.r. (or NMR) is nuclearmagnetic resonance and is determined by means of a Varian A-60spectrophotometer; 1; inh. is inherent viscosity; [M is determined bymeans of standard equipment; infrared spectra are determined by means ofa Perkin-Elmer Model 21 infrared spectrophotometer.

Preparation of Adduct (II) from levopimaric acid (I) Resin acids (100grams, having neutralization equivalent (n.e.) of 305 and containing 89grams (0.295 mole) of levopimaric acid (1)) were mixed with powderedparaformaldehyde (24.6 grams, 0.82 mole) (aqueous formaldehyde has beenused) and mineral spirits (30 ml.) in a 300 ml. three-neck flaskequipped with a paddle stirrer and reflux condenser. The flask wasimmersed in an oil bath maintained at 130 and the mixture was stirredvigorously. The solids fused, or dissolved, to a mobile fluid and then,after about 15 minutes, solids precipitated and the mixture became quiteviscous. Stirring and heating were continued for another 20 minutes. Theflask was removed from the oil bath and ether (100 ml.) was added. Theother insoluble product was removed by filtration and washed with ether(2X50 ml.). The dried product which contained some paraformaldehydeweighed 89.6 grams and accounted for 86.4% of the original levopimaricacid. Same procedure without solvent gives about the same results.Inclusion of solvent, mineral spirits facilitates mixing.

Analysis. Calc. for C I-1 0 n.e. 332.25. Found: n.e. 352.

The filtrate contained 4% of the original levopimaric acid unreacted.The 9.6% unaccounted for was probably converted to6-hydroxymethylabietic acid (III) or other abietic-type resin acids. Inone run the filtrate was treated with lithium aluminum hydride (LiAlH inorder to reduce the hydroxyacids to diols. By this method 66.8 gramsadduct (0.201 mole) and 29.2 grams diol (.09 mole), 99% overall yieldwas obtained. A repeat run gave a yield of 95.4%.

EXAMPLE 2 Preparation of Adduct (II) from Pine Gum. (Lab. Prep.)

Adduct (II) was also prepared directly from crude pine gum. Thefollowing examples will serve to illustrate the process.

Crude pine gum (400 grams, containing 22%, 70.6 grams, 0.291 molelevopimaric acid and 10 water) was mixed with flake paraformaldehyde (35grams, 1.16 mole) in a one liter three-neck flask equipped with aheating mantle, reflux condenser and paddle stirrer. The mixture washeated to reflux at 100 in 15 minutes and stirred vigorously at refluxfor 45 minutes. Heptane (500 ml.) was added, the solution filtered andallowed to stand 72 hours at room temperature for crystallization. Theproduct was isolated by filtration, the cake washed with heptane and thesolid dried to give 61.8 grams of material, n.e. 337 .5 and accountingfor 62.8% of (I) present in the original charge. There was 4.02 grams,5.7% unchanged acid in the filtrate leaving 22.4 grams or 31.3%unaccounted for which was probably converted to hydroxyacid or otherresin acids of the abietic type.

EXAMPLE 3 Pilot Plant Production of Adduct (II) from Pine Gum Adduct(II) was prepared in the pilot plant in a 35 gallon jacketed kettleheated by circulating Dowtherm. Crude longleaf pine gum (81 pounds,containing 17 pounds, 0.056 mole of levopimaric acid) was mixed withpowdered paraformaldehyde (7.5 pounds, 0.25 mole) and water (6.5pounds). The charge was stirred and heated for 55 minutes to reflux. Theheater was shut off but the Dowtherm was circulated for an additional 40minutes to maintain refluxing. The temperature of the charge at refluxwas normally 98.5199.5 C. heptane (12 gallons) was added and the batchwas immediately filtered through a pressure filter and allowed to standfor 48 hours. The adduct was isolated by filtration using a vacuumfilter and washed with heptane. Air drying gave 10.1 pounds of material,n.e. 353, 94% pure accounting for 51% of the levopimaric acid originallycharged.

In a typical recrystallization 23.6 pounds of the crude product wasdissolved in 28.4 gallons of hot benzene, filtered and allowed tocrystallize at 10. Filtration and drying gave 20.2 pounds of product(III), 90.3% n.e. 334.

Distillation of the original filtrate allowed recovery of the solvent,normal turpentine (94-97% of that obtained directly from the gum), and arosin which after steam sparging had color grade WG, softening point(ring and ball) n.e. 350, and hydroxyl equivalent (OI-IE) 1341. This isequivalent to a rosin having a hydroxyl content of 1.2% and should becompared with that of commercial rosin which is about 1%.

7 EXAMPLE 4 In the following example Adduct (II) is converted to6-hydroxymethylabietic acid (III) sometimes referred to as6-methylolabietic acid (III).

CHzOH 11+ an. H01 I Adduct (II) fi-hydroxymethylabietie acid (111)Conversion of the Levopimaric Acid-Formaldehyde Adduct to6-Methylolabietic Acid (111). Recrystallized adduct (II) (33 g., 0.1mole) was dissolved in 50-75 ml. of ethanol (95%) and 6- N hydrochloricacid ml.) was added. The solution after standing hrs. at roomtemperature, was diluted with water until no further precipitationoccurred. The oil which separated, crystallized on standing. The solids(29.9 g.) were taken up in methanol ml.), heated to the boiling pointwhile adding water to the cloud point, seeded with crystalline hydroxyacid, and set aside to crystallize. The mixture was further cooled inthe refrigerator and then filtered; the solid (III) was dried in avacuum desiccator (27.3 g., 83.2% yield), M.P. 166.5168, [a] 48.2,

xethunol Analysis.Calcd. for C H O C, 75.86; H, 9.71%; neut. equiv.,332.47. Found: C, 75.86; H, 9.70%; neut. equiv., 334.0.

The hydroxy acid was reduced with excess LiAlH in ether to the diol. Themixture melting point showed no depression with Diol (VI) from theLiAlH, reduction of the resinous product obtained on longer heating oflevopimaric acid and formaldehyde. See Example 11.

EXAMPLE 5 0112011 CHaOH 6hydroxymethylabietic G-hydroxymethyldihydroacid(111) abietic acid (IV) Another portion of adduct (II) was converted to6- hydroxymethylabietic acid (III) and hydrogenated to 6-hydroxymethylidihydroabietic acid (IV) as follows:

Crystallized adduct (II) (525 grams, 11.56 moles, n.e.

336) was mixed with 1500 ml., 95% ethanol and 150 ml.

the reactor, 5 grams of charcoal added, and filtered hot through apressure filter. The charcoal and catalyst were extracted in acontinuous extractor with ethanol. The combined filtrate and extractwere diluted with water to reduce the alcohol concentration to 50% andheated to to give complete solution, The mass was agitated while coolingto room temperature and then maintained at 5 in a refrigeratorovernight. The product was isolated by filtration and dried on a steambath; n.e. 339. The acid was recrystallized by dissolving in 1475 ml.ethanol, diluting with 1325 ml. water, cooling and filtering to isolateproduct (IV) 505 grams, 96% MP. 189 191. The NMR spectrum of a purifiedsample showed one proton in the vinyl region.

Analysis.Calcd, for C H O n.e. 334.27; C, 75.41; H, 10.22%. Found: n.e.336; C, 75.15; H, 10.28%. Hydroxyl equivalent calcd. 334.57. Found:329.0.

Adduct (II) fi-hydroxymethyltetrahydroabietinol (V) (abietylglycol)(D101) V Adduct (II) (60 grams, 0.178 mole), n.e. 336, was dissolved inml. of dioxane and charged to a pressure reactor with 12 grams ofGirdler G-13 copper chromite powdered catalyst. Hydrogen, 2500 p.s.i.was added and the batch was heated to 275 and the pressure maintained at4000-5000 p.s.i. for 4 hours. The mixture was cooled, removed from thebomb, treated with 5 grams of charcoal, heated to obtain completesolution, and filtered through a pressure filter. The filtrate wascooled and the product, in the form of colorless crystals, was isolatedby filtration. The filtrate was found, by titration, to contain only0.56 gram of acid calculated as (IV). The catalyst in the filter cakewas extracted in a continuous extractor to remove occluded products.Forty grams, 69.6%, of crystalline (V) was obtained. Evaporation of thesolvent from the filtrate gave 15.3 grams of resinous material. Thisrepresents a recovery of 96%. In most runs the filtrate was set up forremoval by azeotropic distillation of the water formed in the reactionas result of interesterification. The water-free filtrate was fortifiedwith more adduct, catalyst added and reduction repeated. There was nonoticeable drop in yield by recycling residual materials 4 times. Thecrude glycol was purified by distillation in vacuo, B.P. 192, 0.2 mm.and crystallization from dioxane; M.P. 179-180". Direct crystallizationfrom dioxane or acetone gave M.P. 1795-181", The glycol was undoubtedly6-hydroxymethyltetrahydroabietinol (V) since it did not absorb ozone andthere were no vinyl hydrogens as evidenced by NMR spectroscopicexamination.

Analysis.-Calcd. for C -H O C, 78.05; H, 11.86%. Found: C, 78.05; H,11.86%. Hydroxyl equivalent caicd.

161.15. Found: 165.6%.

If desired, equivalent amounts of 6-hydroxymethyldihydroabietic acid(IV) may be used as the starting material in place of Adduct (H) in thepreparation of saturated Diol (V) thus completing the fourth step in theseries.

It is also within the scope of our invention to use an equivalent amount(57 grams) of the unsaturated (conj.) diol (VI) (See Example as thestarting material in Example 6 above for the preparation of saturatedDiol EXAMPLE 7 The procedure of Example 6 was repeated except theprocess was scaled up to 360 grams which gave 1290 grams glycol (V) (4.0mole) from the initial reduction of 2520 grams adduct (II) (7.54 mole).Drying the filtrate and reworking resulted in an additional 669 grams(V) (2.08 mole) from a second reduction, given g. a total of 1959 gramsof (V) or an 80.8% yield. An attempt to obtain more glycol from a thirdreduction gave an oil which was slow to crystallize. This was distilledthrough a 12-inch column packed with stainless steel helices. Thedistillate, 392 grams solid, 16.1%, was almost colorless (B.P. constantat 170 C., 0.15 mm.; OHE 260.7). By comparison, tetrahydroabietol (B.P.154, 0.1 mm.) was easily separated from the glycol using the sameequipment. From this evidence this second material is not a mixture ofthe glycol and tetrahydroabictol which might be expected since theelimination of formaldehyde from the adduct during the reaction wouldhave resulted in formation of this alcohol. Crystallization of thedistillate from ethyl acetate gave a crystalline solid (M.P. 100- 101.5which contained one hydroxyl and had no ultraviolet absorbance.

Analysis.--Calcd. for C H O: C, 82.27; H, 12.5%; OHE, 306.9. Found: C,81.73; H, 12.24%; OHE, 298.

EXAMPLE 8 In the following example the saturated Diol (V) is prepared byhydrogenation of a polyester prepared by heating6-hydroxymethyldihydroabietic acid (IV).

A polyester of the hydroxyacid ('IV) was prepared by heating 60 grams(0.18 mole) acid to 275, 0.2 mm. pressure for 2 hours. Molecular weightby end group titration was 1600. The residue, a clear colorless resin,M.P. 227- 232 was dissolved in 120 ml. dioxane and charged to a pressurereactor with 12 grams Girdler G-l3 copper chromite powdered catalyst.Hydrogen was added, 2500 p.s.i. and the batch was heated to 275 for 4hours maintaining hydrogen pressure at 4000 to 5000 pounds. The batchwas filtered and product isolated as in Ex. 6. By titration, thefiltrate contained 0.67 grams of acid (IV) and 50.7 grams (88.5%) ofcrystalline glycol (V), having a M.P. 179-180 C.

EXAMPLE 9 Utilty of 6-hydroxymethyltetrahydroabietinol (V) Usefulness ofthe adduct (II), hydroxyacids (III and IV), was demonstrated by making apolyester of the diol (V) and terephthalic acid.

Dimethyl terephthalate, 9.7 g., 6-hydroxymethyltetrahydroabietinol, 16.7g., cobalt acetate, 4 mg., and lead oxide, PhD, 4 mg, were heated to 250C., 4 hrs. 10 mm. pressure and finally to 300, 12 hrs. at 0.5 mm. Whencold the residue was a brittle glass which was soluble in dioxane andinsoluble in methanol. The original materials were soluble in methanol.The residue was dissolved in 100 ml. hot dioxane and precipitated bypouring into 1 1. cold methanol. Nineteen grams colorless powder wasobtained, M.P. 16870; inherent viscosity, 1; inh. 0.0374 (0.5% dioxane,30 C.). A film cast from dioxane was clear, colorless and brittle. Whenapplied to wood from dioxane a glossy, hard finish was obtained.

EXAMPLE 10 In the following example 6-hydroxymethylabietinol (VI) isprepared by reacting a mixture of Adduct (II) and 1 06-hydroxymethylabietic acid (III) with lithium aluminum hydride (LiAlHThe procedure follows:

THZCH CHZOH I A l/\ U I I LiAlHA I E-CH OHZOH III VI 7 CH2O/130", 140/l4 hr.

l @A in) (ii E-OH 011,0 15-20 min,\.

I CH2 Levopimaric acid (30 g., 0.1 mole) was placed in a flask withparaformaldehyde (6.6 g., 0.22 mole) and stirred with a paddle-typestirrer while heating in an oil bath at After 50 min., dioxane (75 ml.)was added to solublize the materials and the mixture was heated atreflux for about 2 hrs. The mixture was cooled, diluted with ether, andwashed with water. The ether solution was shaken with sodium sulfate,filtered, and evaporated to a light-colored friable resin which was amixture of resin acids, adduct (II) and hydroxy acid (III).

Analysis-Calm. for C H O neut. equiv. 332; active H equiv. (HaE, gramsof sample required to evolve 1 mole of hydrogen on treatment with excesslithium aluminum hydride), 166. Found: neut. equiv., 308; HaE, 194.3.

A 5-g. sample of the material was treated with excess LiAlH in ether andallowed to stand overnight. The mixture was hydrolyzed with excess,dilute, iced hydrochloric acid and the ether solution was washedchloride free l 1 12 with Water. The ether solution was driedover N21 SOfiltered, and concentrated. A pro-duct (VI) having I I A335 243 mu (e23,620) (E 2- l-g- 73.7, M.P. 179.5181.3, was isolated. f

AnaIysis.Calcd. for 0 ,11 ,0 1 0, 79.19; H, 10.76; lA l HaE, 158. Found:C, 79.24; H, 10.63; HaE 170. p Ethanol I The diol (VI) was converted tothe diacetate by either refluxing With excess acetic anhydride or bytreatment of V a pyridine solution of the diol with a slight excess of0001; c0011 acetyl chloride. The diacetate was molecularly distilled 1OAdduct H Saturated gym, at 135 The product was a very viscous, Waterth WWhite liquid, (41); 47.76.

c l f 1-1 0 C 7455; H, 951; Hydrogenation of LevopunancAcid-Formaldehyde sapon. equiv., 201.3%. Found: C, 74.5; H, 9.47%;sapon. Adduct- The lecrystalhzed adduct Was placed 111 equiv 202 alow-pressure hydrogenator with ethanol (75 ml.) and The unsaturated(conj.) diol (VI) may be converted 5% Pa11 adiu111-0I1-E1Tbm1 Catalyst Yto the saturated diol (V) using the general procedure of dlogfinatlonwas allowed t0 p P ovemlght' at -45 Example 6. A mixed melting pointWith saturated diol P- All of the adduct had q v The l f was (V) Showsno depmssiom 2 filtered and the product Was precipitated by addition of0 Water. A semicrystalline material was obtained. The in- EXAMPLE 11frared spectra showed free hydroxyl bands indicating at Conversion ofAdduct II to the formaldehyde adduct least a partial opening of thecyclic ether. The material of abietinol (VII). was redissolved in aminimum of 95% ethanol and al- EH2 EH2 1 I 20 iA1H4 130 alkaline 15-20mmhydrolysis AOOOH COOH CHzOH Tevo imane A cid (I Adduct 11 Abietinol Addu ct (VII) CH2OH i @A l l H 0 CHzOH Abietiliol (c0nj.) (V I) Conversion0 adduct ll to the hydroxy ether.-(The lowed to stand overnight. Acrystalline solid precipitated formaldehyde adduct of abietinol (VII)).Recrystallized (3 g., 20%), M.P. 240.9-243.8 [a] -+l06.5. N0 adduct (10g.) Was slurried in dry ether (.50 ml.) and other pure crystallineproduct was isolated. added to an ether solution of LiAlH, (3 g. in ml.)with 59 Analysis.Calcd. for C H O C, 75.40; H, 20.25%; rapid stirring.The mixture stood 4 hrs. at room temperaneut. equiv., 334.49. Found: C,75.70; H, 10.25%; neut. ture and was then hydrolyzed by cautiousdropwise addiequiv., 337.8. tion of 6 N NaOH until the solids clumped toa granular A quantitative hydrogenation gave a hydrogenation mass. Themixture was filtered; the other solution of the equivalent of 286(calcd. for C H O 332). The low product was concentrated by evaporationand filtered to 60 value may be a result of partial hydrogenation of theyield crystalline (VII) (6.1 g., 60%), M.P. 124-126", second double bondof the hydroxy acid formed during (a) +948 hydrogenation.

Analysis.Calcd. for C H 0 C, 79.19; H, 10.76%. EXAMPLE 13 Found: C79.08'H 10.64%.

The adduct of abletlnol (hydroxy ether) (VII) 01' A Small sample of thehydyoxy .efher 3 dlssolved abietinol adduct prepared by the process ofExample 11 m 3 vol. of ether and shaken with 1 chop of dilute (3 N) maybe converted by dilute mineral acids to con ugated HCl. After about 3mm. crystalline diol precipitated.

a letmol (VI), sometimes referred to as D101 (VI). This is con ugatedabietmol (VI) and exemplifies another Diol VI may be used 1n thepreparation of a Watermethod of the prepamnon of (VI) of the precedmgresistant film-forming polyester The process follows example as Well asa utility for the adduct of Abietinol (VII). A mixed melting point withgood diol showed no depression.

EXAMPLE 12 In the following example Adduct (II) of Example 11 ishydrogenated to give saturated cyclic ether (VIII).

Diol (VI) (conj) (7.95 g., 0.025 mole) Was mixed with benzene (45 ml.)and diethylaniline (5 ml.) and a solution of sebacylchloride (5.51 g.,0.023 Wide) in benzene (10 ml.) was added. The mixture was stirred untilall the diol had dissolved and then held at room temperature overnight.The reaction mixture was washed with 13 V 14 dilute hydrochloric aciduntil all the diethylaniline had rubbers. As evidenced by Experiment 4,useful plastics been removed, dried over sodium sulfate, filtered, andcan be btained, evaporated to a resinous mass. The resin was extracted Wl i with acetone, leaving an insoluble oil which dried to a 1. Aformaldehyde-levopimaric acid adduct having the rigid foam in the vacuumdesiccator. The foam was soluformula:

ble in dioxane and had an inherent viscosity of 0.16 at 0.5%concentration. The foam was melted to a clear resin and spread in a thinfilm on a piece of clear, bare wood. A film was also applied to the woodby evaporation g CH; of the dioxane and chloroform solutions of theresin. After standing overnight the piece of wood was sub- Hz '4 2merged in water for hours. At the end of this time all CH3 films werestill clear and tough, showing no signs of mo 3 1% (I) whitening.

EXAMPLE 14 15 In the following example 6-hydroxymethyltetrahydro- H aabietinol (a saturated diol) (V) is used to replace in part 00011 thecustomary glycols used in the preparation of polyurethane foams andrubbers.

Example 33 i". ??:::a:::::::::::: lifffflii: gf" Polyethylene (.01mole)-.. (.02 mole) Glycol 200, g. 2.0- 4.0- 0 0. Polypropylene (.01mole)..... (0.003 mole). Glycol 2000, g 0 0 20.0 10.0.Toluenediisocyanate, g (.02 mole) Procedure 2. A formaldehyde adduct ofabietinol of the formula:

(1) The glycols were dissolved in 8 ml. dioxane or toluene, heated to areflux to expel air and flushed with M gas. The diisocyanate was addedbelow 70 C., CH3 blanketed with M gas and heated to 100 for 20 min. IThe clear solution was poured into a petrie dish to cast H2 CH2 fi s afilm. This was cured on a hot plate at about 120 C. 0 CH3 9 on CH3 forseveral hours. At 120, the film was soft enough to 1120/ dent easily. Il l 2 This was handled like (1 At 120 c. 1 was CH: harder than (2). C CgIn experiments 3 and 4 the glycols were heated to dis- \CmOHH solve theabietyl derivative and degassed. After blanketing with H; thediisocyanate was added and the batch heated to Q for 20 3. A continuousprocess for the preparation of the levo- In each of the 9 f e i one 9Pof n'morphelme pimaric-formaldehyde adduct (II) from the levopimaric wasadded and surfed 1n P t0 castlng the filmsacid component of crude pinegum which comprises the Films were cast on aluminum sheets and heated tosteps; eul'e asin Example (a) mixing crude pine gum containing about0.056

The results fellow: mole levopimaric acid with 0.25 mole powdered para-Barcol Hardness of films: Experiment 1:80; 2:15; 3 f ld h d and 03 5mole water; was viscous and sticky, hardness=0; 4 tough, rubberyStirring and heating the mixture to fl and hardness=75. All the filmswere clear and colorless. 5 maintaining a period f dwell at refluxtempera- Samples of 1, 2 and 4 were dissolved in N,N-dimethyl- 93 100 Cf about 40 60 minutes; formamide and Precipitated y Pouring into meth-(d) adding about 310 mole heptane and immediately anol. The precipitateswere dried in vacuo 0.5 mm., 50 C. filt i the mixture in a pressure filtDMF (e)a holding the filtrate with gradual cooling for 45-50 ours; for(l), 0.17; (2) 0.244; (3) not determined; (4) 0.244. (f) isolating theadduct (11) by vacuum filtration;

It will be observed that Diol (V) (abietyl glycol) may and th ft be usedto harden and improve polyurethanes from poly- (g) recovering theisolated Product by drying ethylene and polypropylene glycolethers-materials currently being used in numerous polyurethane foams and(References on following page) 15 16 References Cited Moore et 611., J.Amer. Chem. Soc., vol. 81, pp. 458-60 UNITED STATES PATENTS Parkin 5t31., J. Org. 0116111., V01. 30, pp. 2356-8, July 4/1963 Schuller et a1.260-5145 XR 9 7/1963 Kincl et a1 260514.5 XR 10/ 1966 Patrick et a].260514.5 XR 5 HENRY R JILES, Primary Examiner 10/1967 Schuller et a1.260-5145 3/1968 Summers et a1... 260-514.5 XR FORD ASSSantEXammer OTHERREFERENCES U.S. C1. X.R.

Fieser et a1., Steriods, Reinhold Pub. Co., New York 10 2602, 75, 77.5,5145,6175 (1959), P. 698.

